The competitive nature of the building industry has led to a need for cost-effective methods of construction. As is well known, cost effectiveness is achieved by simplicity and efficiency in construction. A major component of the cost of building is labour, those skilled and unskilled. This is particularly so in first world countries such as Australia and the United States.
Prefabricated components such as frames and panels and even fully prefabricated structures in knockdown form have been used. The aim of these concepts is to achieve a structure that can be rapidly assembled on site by non-skilled labour.
These concepts have faced a number of difficulties. One particular difficulty is the fact that building standards vary considerably throughout regional and geographic areas. An example of this is wind-loading standards for roofing and wall structures which vary significantly throughout a country such as Australia. These standards include specific requirements in cyclone rated areas.
The problem with the conventional concepts is that they are generally incapable of complying with such a variation in requirements.
The present inventor has previously developed a steel reinforced concrete wall construction system. Fibre reinforced cement sheet is supported on a steel frame wall to define a substrate for sprayed concrete. This system was a development of a method for forming screeded reinforced concrete walls in underground excavations such as car parks.
Australian patent number 708031 requires skilled labour to erect steel wall framing on site. This entails substantial design work depending upon building code requirements for differing geographical regions. Furthermore, the flexibility of the structure during application of the sprayed concrete induces a degree of thixotropy to the applied layer in some cases causing it to flow downwardly on the fibre cement sheeting support substrate.
The present inventor has also developed an improvement to the system used in Australian patent number 708031. This improvement includes a panel assembly for a building structure including a support frame that is mountable on a substrate, structural sheeting provided on the support frame so that the support frame and the structural sheeting define a zone for a cementitious material, a layer of cementitious material positioned against the structural sheeting to fill the zone and at least one post-tensioning member that extends through the layer of cementitious material with predetermined tension applied to the member.
The present inventor has now furthered the invention to simplify construction and increase efficiency.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.